Quiz 607: Geography for Civil Services Examinations
1. Which among the following phenomena has been largely responsible for the recent drought in Somalia and northern Kenya?
[A]El Nino Southern Oscillation
[C]Indian Ocean Dipole
[D]A collective impact of all the above three
2010, a strong La Niña cooled surface waters in the central and eastern Pacific Ocean, while allowing warmer water to build in the eastern Pacific. The pool of warm water in the east intensifies rains in Australia, the Philippines, and Indonesia. Domino-style, this pattern also increases the intensity of westerly winds over the Indian Ocean, pulling moisture away from East Africa toward Indonesia and Australia. The result? Drought over most of East Africa and floods and lush vegetation in Australia and other parts of Southeast Asia.
2. Which among the following biogeographical boundary kept the fauna of Indomalaya ecozone and Australasia Ecozone isolated from one another contributing to the distinctly different fauna of Australasia?
[A]Strait of Malacca
[B]Strait of Lombok
Strait of Lombok
Strait of Lombok is part of the biogeographical boundary between the fauna of Indomalaya ecozone and the distinctly different fauna of Australasia. The boundary is known as the Wallace Line, for Alfred Russel Wallace, who first remarked upon the striking difference between animals of Indo-Malaysia from those of Australasia and how abrupt the boundary was between the two biomes.
3. Recently, it has been discovered that Earth is not alone in its orbit around the Sun. There is a small ‘Trojan’ asteroid 2010TK7. Why this Trojan Asteroid does not collide with the earth ?
[A]Because the asteroid and earth are constantly on the same orbit
[B]Because the asteroid and earth are on different orbits
[C]Because Trojan Asteroid revolve around the earth like satellite
[D]None of the above reason.
Because the asteroid and earth are constantly on the same orbit
A Trojan asteroid shares an orbit with a larger planet or moon, but does not collide. So a Trojan has a particular position in a stable spot – either in front of a planet or behind it called Lagrangian points. Because the asteroid and planet are constantly on the same orbit, they can never collide.Trojan asteroids were anticipated in earth’s orbit but never discovered yet. Nasa discovered the asteroid, which lies 80 million km from Earth, using its Widefield Infrared Survey Explorer (WISE) telescope. Astronomers have long thought that Earth did have Trojans but their discovery has proved elusive because they can’t be seen in daylight.
4. Consider the following scientific observations over geological times:
1. Moon is moving away from Earth
2. Earth is moving closer to Sun
3. Mean solar day is getting longer
4. Earth’s rotation speed is getting down
Which among the above observations are correct:
[A]1 & 2
[B]1, 2, 3 & 4
[C]1, 3 & 4
[D]1 & 4
1, 3 & 4
This question has been carefully framed over the concept of tidal acceleration. Due to tidal friction or tidal acceleration, over geologic time, the moon recedes from the Earth, at about 3.8 centimeters (1.5 in)/year, lengthening the terrestrial day. Here is the reason reproduced from wikipedia. Because the Moon’s mass is a considerable fraction of that of the Earth (about 1:81), the two bodies can be regarded as a double planet system, rather than as a planet with a satellite. The plane of the Moon’s orbit around the Earth lies close to the plane of the Earth’s orbit around the Sun (the ecliptic), rather than in the plane perpendicular to the axis of rotation of the Earth (the equator) as is usually the case with planetary satellites. The mass of the Moon is sufficiently large, and it is sufficiently close, to raise tides in the matter of the Earth. In particular, the water of the oceans bulges out along both ends of an axis passing through the centers of the Earth and Moon. The average tidal bulge closely follows the Moon in its orbit, and the Earth rotates under this tidal bulge in just over a day. However, the rotation drags the position of the tidal bulge ahead of the position directly under the Moon. As a consequence, there exists a substantial amount of mass in the bulge that is offset from the line through the centers of the Earth and Moon. Because of this offset, a portion of the gravitational pull between Earth’s tidal bulges and the Moon is perpendicular to the Earth-Moon line, i.e. there exists a torque between the Earth and the Moon. This boosts the Moon in its orbit, and decelerates the rotation of the Earth. So the result is that the mean solar day, which is nominally 86400 seconds long, is actually getting longer when measured in SI seconds with stable atomic clocks. (The SI second, when adopted, was already a little shorter than the current value of the second of mean solar time.) The small difference accumulates every day, which leads to an increasing difference between our clock time (Universal Time) on the one hand, and Atomic Time and Ephemeris Time on the other hand: see ΔT. This makes it necessary to insert a leap second at irregular intervals. In addition to the effect of the ocean tides, there is also a tidal acceleration due to flexing of the earth’s crust, but this accounts for only about 4% of the total effect when expressed in terms of heat dissipation. If other effects were ignored, tidal acceleration would continue until the rotational period of the Earth matched the orbital period of the Moon. At that time, the Moon would always be overhead of a single fixed place on Earth. Such a situation already exists in the Pluto-Charon system. However, the slowdown of the Earth’s rotation is not occurring fast enough for the rotation to lengthen to a month before other effects make this irrelevant: About 2.1 billion years from now, the continual increase of the Sun’s radiation will cause the Earth’s oceans to vaporize, removing the bulk of the tidal friction and acceleration. Even without this, the slowdown to a month-long day would still not have been completed by 4.5 billion years from now when the Sun will evolve into a red giant and possibly destroy both the Earth and Moon. (Tidal acceleration and solar mass loss is also moving the Earth outward from the Sun, but it is unknown whether it will be enough to save it from destruction.)
5. Sun is vertical at least once in a year at which among the following cities of India? (given is Latitudes Chennai: 13°5′2″N, Mumbai: 18°58′30″N, Nagpur: 21°04′N, Jaipur: 26°55′34″N)
Choose the correct option:
[B]1 & 2
[C]1, 2 & 3
[D]1, 2, 3 & 4
1, 2 & 3
This question is very simple but wants you to apply your knowledge of the torrid zones, temperate zones and Frigid zones. We know that the tropic of Cancer currently lies 23° 26′ 16″ north of the Equator. The Tropical zone or torrid zone is located between 23½°N and 23½°S. The sun is vertical at least once in a year at EVERY place in this zone. In the above question, the three cities viz. Chennai, Nagpur and Mumbai fall within this definition and are thus located in Torrid Zone. So the correct answer is these three cities. Please note that in temperate zone which lies from 23½°N to 66½°N and 23½°S to 66½°S , sun is NEVER vertical. In the frigid zones, the length of the day or night at least once in a year is hour duration.
6. If place X and Place Y, both located on equator, are at a distance of 18520 kilometers, the approximate difference between their longitudes will be ____?
We all know that a minute of arc on the planet Earth is 1 nautical mile. 1 nautical mile is 1852 meters or 1.852 kilometers. To travel around the Earth at the equator, we would have to travel (360 * 60) 21,600 nautical miles, 24,857 miles or 40,003 kilometers.
The question says that the distance between point X and Y is 18520 kilometers , which means that they are 10000 nautical miles apart. So, if 21620=360°, 10000=166.5°. So correct option is C
7. Over a longer duration, which among the following factors cause the satellites experience a reduction in the altitude (orbital decay)?
1. Atmosphere of Earth
3. Earth’s gravitation
Choose the correct option:
[B]1 & 2
[C]1, 2 & 3
[D]2 & 3
1, 2 & 3
This is a simple question asking about reasons of orbital decay. The satellites particularly in the LEO are subject to a drag produced by an atmosphere due to frequent collisions between the satellite and surrounding air molecules. The amount of this drag keeps increasing or decreasing depending upon several factors including the solar activity. The more activity heats of the upper atmosphere and can increase the drag. This drag in a long duration causes a reduction in the altitude of a satellite’s orbit, which is called orbital decay. So, the major cause of the orbital decay is Earth’s atmosphere. The result of the drag is increased heat and possible reentry of satellite in atmosphere causing it to burn. Lower its altitude drops, and the lower the altitude, the faster the decay. Apart from Atmosphere, the Tides can also cause orbital decay, when the orbiting body is large enough to raise a significant tidal bulge on the body it is orbiting and is either in a retrograde orbit or is below the synchronous orbit. Mars’ moon Phobos is one of the best examples of this. Whenever two masses orbit each other, the combined effect of the space-time curvature of the moving objects produces gravitational waves which carry away orbital energy. For small masses this effect is negligible, but for very massive objects like black holes and neutron stars the energy carried away can be rapid enough to cause their orbits to spiral in on each other, eventually merging the two masses. Thus gravitation is also a cause behind the orbital decay.
8. The pointer or arrow of the magnetized needle of a compass indicates which among the following?
[A]Geographic North Pole
[B]Magnetic North Pole
[C]Geo-magnetic North Pole
[D]Magnetic South Pole
Magnetic South Pole
The north pole of a magnet in a compass points north because it is attracted to the Earth’s magnetic south pole, which is located near Earth’s geographic north pole. The geographic north pole of earth corresponds to magnetic south pole and geographic south pole of earth corresponds to magnetic north pole. The direction in which a compass needle points is known as magnetic north. This is not exactly the direction of the North Magnetic Pole. Instead, the compass aligns itself to the local geomagnetic field, which varies in a complex manner over the Earth’s surface. The angular difference between magnetic north and true north (defined in reference to the Geographic North Pole), at any particular location on the Earth’s surface, is called the magnetic declination. Most map coordinate systems are based on true north, and magnetic declination is often shown on map legends so that the direction of true north can be determined from north as indicated by a compass.
9. Which among the following is the lowest level of a body of water such as an ocean or a lake?
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub- surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many suchorganisms are permanently attached to the bottom.
10. Which among the following methods of heat transfer is maximum responsible for heating of the lower layers of the atmosphere near earth’s surface?
[A]Radiation from Sun
[B]Radiation from Earth
Radiation from Earth
Radiation from Sun comes to earth in the form of smaller waves and earth being cooler body, gives off energy in the form of long-wave. These are then radiated back to the atmosphere. This this Long-Wave Radiation from the earth’s surfaces heats the lower layers of the atmosphere. The Atmospheric conduction occurs at the interface of (zone of contact between) the atmosphere and the earth’s surface. However, it is actually a minor method of heat transfer in terms of warming the atmosphere since it affects only the layers of air closest to the earth’s surface. This is because air is a very poor conductor of heat. ‘ When the pockets of air near the surface are heated, they expand in volume, become less dense than the surrounding air, and therefore rise. This vertical transfer of heat through the atmosphere is called convection, and is the same type of process by which heated water circulates in a pan while heating. The currents set into motion by the heating of a fluid (liquid or gas) make up a convectional system. Most vertical transfer of heat within the atmosphere & Oceans occurs via Convection and is a major cause of clouds and precipitation.